Process for manufacturing artificial stone.



of time.

UNITED STATES PATENT OFFICE.

JACOB STAUDT, OF BONN, GERMANY.

PROCESS FOR MANUFACTURING ARTIFICIAL STONE.

residing at Bonn-on-the-Rhine, 64 Arndt-' strasse, Germany, have invented certain new and useful Improvements 1n Processes for Manufacturing Artificial Stone; and I do hereby declare the following to be a full, clear, and exact descri tion of the invention, such as will enable ot ers skilled in the art to which it appertains to make and use the same.

M invention refers to the manufacture of artiiibial stones and more especially is an improvement upon the process described in my Patent, No. 797,624 of August 22nd, 1905.

The process described in the patent referred to, consists in subjecting a powdery mixture of a stone-filling substance, (e. g. quartz-sand, ground feldspar, ground glass, emery, and the like), and a binding medium, (e. g. oils, fats or waxes) to the action of the air at a suitably elevated temperature (about 85 to 150C. according to the binding material employed) for a certain period Thereby, a stiffening of the mass is produced to such an extent, that it can be ressed into molds, the artificial stones thus ormed hardening in a short time at suitable temperatures, (about 150 to 200 C).

By experiment I have found, that I can considerably reduce the duration of the stiffening and hardening process, if I allow sulfur to act upon the binding medium before subjecting it to the influence of the air to ther with the filling substances.

l arn aware that compounds of sulfur, a filling substance and an oil are already known. But in these compounds sulfur in the free state is the main constituent and the oil only plays the part of a dilutive agent. Moreover in their composition the stiffened, dry but easily compressible powder is absent which alone renders practicable the method described in my prior patent, No. 797,624, August 22, 1905.

By the addition of sulfur, according to my present invention, I intend to act upon the oily and fatty binding media in a similar Specification of Letters Patent.

Application filed September 18, 1905.

Patented March 24, 1908.

Serial No. 278,945.

stituent, but only an exceedingly small quantity of free sulfur.

Sulfur possesses a greater orless clen cal affinity to the oily, fatty andwaxy binding media, which are employed in the present process. With some of these substances an addition of 20 to 25% of sulfur or an easily decomposable sulfuric compound as for instance chlorid of sulfur is sufficient to cause a violent chemical reaction by which they are converted into solid rubberlike mamas. With others 50% of sulfur or sulfuric compounds have to be added to produce the same result. Such solid masses are usually termed vulcanized oils.

In my present process however I prefer not to add such large quantities, because the formation of rubberlike masses from the binding substances and sulfur would prevent the production of the powderlike intermediate material which forms an essential feature of the process of my Patent No. 792,624, August 22, 1905. I prefer to employ sulfur in such quantities only that the reaction is less violent and that the effect of the sulfur upon the oily and fatty binding media is merely to convert them into masses of more or less viscous quality, such as are ca able of forming a moist powder together wit filling substances, which when heated and subjected to the influence of the air attains a condition in which it can be molded by roces's can be converted into liar odies by ieating to temperatures up to 200 C. Such binding media may there ore be designated as partially vulcanized.

The advantage gained by the chemical reaction of the sulfur upon the binding media, as compared with the invention of my Patent No. 794,624, August 22, 1905, consists mainly in an acceleration of the stifi'ening process, because the vulcanized binding media, in order to acquire the desired degree of stiffness, need only be subjected to the action of the air for a much shorter time than non vulcanized substances. This advantage is especially important with mixtures requiring large quantities of binding medium in consequence of the employment of filling materials capable of absorbing large quantities of binding substances, such as for instance, silicious marl. The employment of large quantities of binding medium gives the finished product a hornlike or ebonitelike consistenc The reduction in theduration of the sti ening process is however of course also a substantial advantage with mixtures in which filling substances are emplo ed that 5 require only small" uantities of bin ing medium. Moreover t e vulcanization of the binding substances produces greater hardness'in the binding substances and in consequence also in the finished products.

In. order to obtain a suitable action of the sulfur upon the binding substances -I may proceed in different Ways:

1. I mix finely ulverized or sublimated sulfur with the pufirerized stone-filling substances, e. g. with finely powered quartzsand, quartz-powder, ground felds ar, or lime-spar, ground glass, emery, car orundum, Vienna-lime, kieselguhr or silicious earth. Then the mixture is moistened with the binding medium, which consists of oils, fats, varnishes, animal or vegetable waxes e. g. linseed oil, linseed oil-varnish, rape-oil, blubber-oil, tallow, palm-oil, or heavy rosinoils, whereu on the mass is heated. Thereby, the fine y-divided sulfur combines with the surrounding particles of the liquid bind: ing medium.

2. I stir pulverized or sublimated sulfur into the heated binding medium, whereby the chemicalcombination is brought about and then moisten the filling substances with the vulcanized binding medium.

, 3. I dissolve sulfur in any one of its known dissolvents, stir the solution into the heated 85 binding material and then moisten the filling uenceof its greater aflinity to the oily and atty binding materials and efiects their vulcanization, and then moisten the filling substances with the mixture.

In all these cases by subse uent continuous heating of the moist ow 'er I obtain a violent reaction of the su ur with the bind} 'ing substances during the stiffening process, easily recognizable by the powder acquiring adarkbrown to black color. This reaction completes andpartly replaces the subse uent action of the oxygen of the air upon the inding substance and, thereby efiectsthe reduction in the duration of the'stiifening rocess. When binding substances are use which react'u on sulfur very violently, such as linseed oi rape seed oil or train oil, I prefer to retard the reaction by first combining the sulfur with a binding substance that reacts less violently such as for instance resin oil or cotton seed oil and then to addthe binding substance which reacts more violently. When chlorid ofsulfur is used a too violent reaction can be avoided by dissolving the by proceeding as follows.

* scribed.

seams ,chlorid of sulfur in carbonic disulfid or in purified mixture.

Good results may be obtained for instance 100 parts by 7 weig t of so-called kieselguhr (silicious earth) is mixed with 15 to 20 parts by weight of sublimated sulfur and arts by weight of one of the oily or fatty binding substances, e. g.; linseed oil; The mixture is stiffened at 75 a temperature between 140 and 160 C. in the manner there described. Then theimass thus obtained is pressed into molds and the molded blocks hardened at a temperature of petroleum before adding it to the 160 to 180 C. The molded pieces thus pro- 3 duced have the color, ap earance, fracture and approximately also t e specific gravity of ebonite.

By suitably selecting the proper stone-filling substances, (e. g. by the employment of 5 finely powdered sand, feldspar, glass), a material of stone-like consistency and of great hardness can be obtained; if filling substances are selected, which possess electrically insulating qualities, the molded pieces thus produced are excellently adapted for insulating purposes.

Having thus described the nature of my said invention, and the best means I knowof carrying the same into practical effect, I 5

claim:

1. The herein described process of manufacturing artificial stone, which consists in mixing a ulverized stone-filling material with an oxldizable and vulc'anizable oily or fatty binding agent, sulfurizing or partly vulcanizing said binding agent, stiffenin the mixture by exposing it to the action 0 the air at an elevated temperature, and then molding the mixture into stone; substantially as described.

2. The herein described processof making artificial stone, which consists in stiffenin a mixture of a sulfurized or partly vulcanize oxidizable oily or fatty bindin agent and a pulverized stone-filling materia by exposing said mixture to the action of the air at an elevated temperature, and thereafter molding the mixture into stone; substantially as described.

3. The herein described process of making artificial stone, which consists in stiffening a mixture ofa sulfurized or partly vulcanized oxidizableoily or fatty agent and pulverized filling material by exposing said mixture to 120 the action of the air at an elevated temperature, and thereafter moldin the mixtureinto stone, the hardening of t e stone being accelerated by heating; substantially as de- 4. The herein described processof making artificial stone, which consists in mixing a refractory pulverized material with an oily or fatty binding agent, adding a sulfurizing or vulcanizing agent, the three materials in 30 quantity being suflieient to produce a moist loose powder, stiffening the mixture by exposing it to the action of the air at an elevated temperature, and thereafter molding the mixture into stone; substantially as (lescribed.

5. The herein described process of manufacturing artificial stone, which consists in mixing 100 parts by weight of kieselguhr with from 15 to 20 parts by weight of flowers ol sulfur and with 75 parts by weight of linseed oil, heating the mixture until vulcanizati'on takes place,- and exposing it to the'ac- 1 tion of air, as long as its plasticity 1s preserved-and thereafter molding the mixture into 1 stone; substantiall as described.

In testmcny w ere-0f I have affixed my signature, in presence of two witnesses.

J MK )B STAUDT Witnesses:

JEAN GRUNI), CARL GRUNI). 

